In the manufacture of chopped fibers from continuous fiber(s), such as glass fiber, molten glass is extruded through tips or holes in the bottom of a bushing, forming beads at the end of the tips or the exposed side of the holes. Once beads of the molten glass have formed at the end of the tips or holes and when the beads reach a certain size, the forces of, surface tension, wetting, and viscosity of the molten material holding the bead to the bottom of the tips or holes are overcome by gravity and the beads fall, each bead trailing a continuous, coarse, primary fiber behind which is attached at its other end to the molten glass in the tip or hole from which the bead came. These primary fibers are usually sprayed with a cooling water mist after they move out of the immediate area below the tip plate of the bushing in a known manner. The primary fibers continue to form as the weight of the beads and primary fibers pull down through holes in the floor of the fiber forming room and into a waste system, usually located in a basement or lower level.
Once all of the tips or holes have thus “beaded out”, the array of primary fibers from that bushing is ready to be gathered into a fiber bundle, i.e. a strand, and started into a chopper or other device that will pull the strand of fibers at a high speed to attenuate the molten meniscuses forming the fibers very near the tips or holes to a desired fiber diameter and then will also chop, wind or otherwise process the fibers, strand or strands of fibers into a desired product form. Normally, the fibers will also be pulled over or past an applicator that will apply a coating of chemical sizing onto the wet fibers prior to chopping in a known manner.
After a bushing has been in service a few weeks or months, the tips get out of alignment with the cooling means and often a few tips will have a lower molten glass flow rate than the other tips. To accelerate the bead down time of these tips the operator will move the array of primary fibers back and forth to attach the slow beads to primary fibers and pull them down to get a primary fiber from all tips and a strand ready to start. Until the primary fibers are started into a puller, chopper, winder, etc., they usually continue to move and fall into a scrap pit or area beneath the floor of the fiber forming room.
For a number of reasons, fibers tend to break all too frequently, usually near the end of the tips in the bushings. Particularly with E type glass, when one fiber breaks it is most always only a matter of a minute or a few minutes until the entire array of fibers from the bushing is broken out and then generating primary fibers scrap. Even in cases where broken fibers do not form beads or break out the remainder of the bushing, by design, it is nevertheless prudent to break out the entire bushing and restart it after a small number of fibers have broken to maximize efficiency and to reduce variation in the product being produced.
The portion of the continuous fiber making process of starting a strand of fibers from all of the tips of a bushing into choppers or other processing equipment is often done by hand and is labor intensive. It also can cause minor injuries to the hands and is usually abrasive to the hands. Thus, it is desirable to enhance this procedure by making it easier and more effective to avoid injuries, hand abrasion, and false starts and to improve productivity thus reducing labor cost and overhead costs by increasing the percentage of time each bushing is producing good chopped fiber products and to reduce raw material and energy costs by reducing primary fiber scrap.